The present invention relates to a snorkel mast, particularly a snorkel mast for a submersible vehicle.
The large areas of offshore continental margin presently being surveyed for the oil industry has led to the use of small craft deployed from a mother ship and provided with adequate power to keep station with it. This is a more cost effective approach than using the mother ship alone. However the crew of such small craft are subject to arduous conditions and operation is often weather limited. It has been suggested to use radio-controlled unmanned vehicles but these gave steering and control problems.
The present approach is to use a remotely controlled, diesel engined, snorkel ventilated, submersible vehicle as the survey platform. Existing technology of snorkel masts of full scale submarines is unsuitable to the smaller robot type craft envisaged. For one thing, the snorkel tube closure valves in use on full size submarines acts too slowly to be fully effective in smaller craft where the size scale is different and further since the snorkel mast of a robot submersible is virtually always above water during operation of the submersible (the snorkel mast doubles as a mounting site for a radio telemetry antenna, a strobe light and a radar transponder) it is necessary to ensure that the snorkel mast will not affect the stability of the surveying platform provided by the submersible vehicle, particularly in turns.